Biology, Module 12, Phylum Arthropoda

Quizlet Vocabulary Game, M12 
Videos, etc, for M12

Wow, these phyla and class names just keep getting better and better!
Arthropoda?  Well.....   okay.
We've got more stuff about invertebrates in this module, but only about a specific phylum.
The organisms of Phylum Arthropoda all have:

• an exoskeleton (that they shed/molt -- until they are adults -- as the body grows and needs a larger exoskeleton)
• body segments (head, thorax, abdomen, OR, cephalothroax, abdomen)
• jointed appendages (not just the legs, but also the chelipeds - claws)  Chelipeds (peds - feet) make me think of jelly shoes, lol.  We called them jellies. 
  So... arthropoda... arthro means jointed, poda is talking about a leg or foot... Yep, that word does mean something after all!
  
• a ventral nervous system (ventral means on the belly side) For more protection, that's where God put the nerve cord, unlike our spinal cord that has a protective backbone.
• and most interesting to me, an open circulatory system

I had never heard of an open circulatory system!  No, it does not mean that their veins are open to the air, or even that you can see their veins.  It means their blood is pumped upwards within short vessels, then allowed to just wash down over all the their innards instead of being enclosed in veins.  lol, I like that word.  Innards. 
This process was carefully designed, however, by the Great Designer.  These blood vessels empty into specific body cavities, not just a free-fall to where ever.  God knows what he's doing.  (And He did not need to use evolution -- He is Super-intelligent enough to get it right the first time!)  =)

"Sparky" - covered in dirt

The first organism we studied in this chapter was a crawdad.  The text calls it a crayfish, but admits it can be a crawdad.  Someone must have lived in the south!  lol.  =D  (Thank you, proofreader!) hee hee!
What was really cool was that right after we finished this module, the girls brought some dark dirt up from the creek to put in their flowerbed, and they found a small crawdad in the dirt.  =)

Jellies -- these are not his size.

It was missing one of its jelly shoes chelipeds and one walking leg, but we had learned that when that happens, a membrane seals off the opening so the crawdad will not die from blood loss.  Also, we knew that the crawdad can regenerate it's missing appendage!  Yay!
The girls were glad because Sparky needs his legs and chelipeds.
Yes, they named it.  =D  And yes, we did return him. 


While we were trying to get pictures of Sparky in his sour cream container, he got turned over.  I told Bethany to make sure he stays upright.  Rebekah knew that because of the open circulatory system, he needed to stay upright or his blood would pool up in his dorsal side (back side -- opposite of belly -- not backside like its rear).  Gravity, ya know. 
So now Bethany will not need this to be explained when she gets to Biology.  Younger siblings' exposure to older siblings' discussions is really beneficial in homeschooling!  =)
JohnDavid already knows so much about various aspects of science that since I'll have already studied Physical Science and Biology, I'm looking forward to effortless science for the next few years.  Effortless?  Well, one can hope!  =)

We also leaned about Sparky's respiratory system, circulatory system, digestive system, nervous system, and reproductive system, only we didn't know it was about Sparky at the time.  His poor kin-folk!  lol.  
There was also a dissection to be done, but I, personally, have never done a dissection.
I guess I could follow the directions, but not remembering anything about Biology except those leaves I've mentioned before, I opted to simply find pictures online, or maybe even a virtual dissection.  (Links to those are at Homeschooler's Resources).  I think when the twins do Biology, I might try it.
Maybe they won't remember Sparky.

This is what Rebekah thinks of pictures of dissections.  =D

I'm glad we had not found Sparky yet.


Next in our module:

• Class Arachnida (spiders)
• Classes Chilopoda (centipedes) and Diplopoda (millipedes)  Again with the poda - foot. 
• Class Insecta (bet you can't figure that one out!)  =)

►These all have exoskeletons, segmented bodies, jointed appendages, ventral nervous systems, and open circulatory systems.
The module went into more detail with the insects than spiders, millipedes, and centipedes.
We learned the specifications to be an insect, (I didn't qualify, although I think I did have wings once... along with my halo, hee hee!) and what kinds of wings they might have, their respiration, circulation, feeding habits, reproduction and development.
We also were to classify some insects the way we learned to in Module one.
Kingdom, Phylum, Class, Order, Family, Genus, Species.  We only did the ones in the book. 

Would you have ever thought of an ant as being in the same phylum as a crawdad?

sMiLeS,